While compound bows have been a development of relatively recent times there are many disadvantages remaining with the improvement over conventional simple bow structures including the bow string being attached to each end of a flexible bow member. A compound bow structure does permit a reduction in pull force so that the archer can more accurately aim the bow because the reduction in tension permits a more steady holding of the bow. The advantageous aspect of a compound bow structure is that it permits the storage of energy into the bow structure thereby limiting the amount of force necessary for the archer to hold the bowstring in the fully pulled position. As an example if a bow requires a draw-force of 80 lbs. the archer must be able to pull the bow string with an 80 lb. force and in a conventional bow he would be required to sight the bow while holding the string against such a force. A presently known compound bow structure having a full force of 60 lbs. would likely require a pull force of approximately 30 lbs. in the shooting position. Obviously this is a significant advantage to the archer in his effort to maintain the bow steady while aiming at a target.
A problem prevalent in the use of compound bows, however, is the accidental breakage of the bow by an overly enthusiastic archer. This problem results from the fact that the bow limbs of a compound bow are generally relatively short and stiff as compared to the limbs of a standard bow having substantial length. The shorter and stiffer limbs are more susceptible to breakage when the archer is supplied with a particular mechanical advantage in pulling the bow string to the drawn position.